`changed columns` fires on a change, and a first evaluation is not one:
a grid built after the window had settled at its size never said how
wide it was, so Rust placed month headings for the one column it was
told about at start-up — every month began a row, and was announced
wherever its first cell fell, mid-row included. Opening a collection
showed "October 2025" stranded over a row of August.
dtourolle
2afc2a7890
